[FW][FIX] config: Avoid compiling test files

[fw-bot]

Description:

Currently, when running a build:* script, we compile both src and
test files from TS to JS.
There is no need to compile the test files as the step is only useful to
utlimately rollup the src files.
Furthermore, the test files (and src) are recompiled by jest when
running the tests.

Benchmark

before : rm -r dist && time mpm run build:js
real 0m8.321s
user 0m15.928s
sys 0m0.290s

after : rm -r dist && time npm run build:js
real 0m5.563s
user 0m11.454s
sys 0m0.176s

---

[FIX] config: Feed dedicated tsconfig.json file to jest
Since 457fe70, we changed stopped compiling the .ts files in the
tests folders to save compilation time. Unfortunately, jest was using
the very same file to compile (via ts-jest) and it actually needs to
compile tests/setup/jest.setup.ts to work properly.

This commit introduces a new dedicated tsconfig file for ts-jest in
order to retain the improvements of 457fe70.

description of this task, what is implemented and why it is implemented that way.

Odoo task ID : TASK_ID

review checklist

• feature is organized in plugin, or UI components
• support of duplicate sheet (deep copy)
• in model/core: ranges are Range object, and can be adapted (adaptRanges)
• in model/UI: ranges are strings (to show the user)
• undo-able commands (uses this.history.update)
• multiuser-able commands (has inverse commands and transformations where needed)
• new/updated/removed commands are documented
• exportable in excel
• translations (_lt("qmsdf %s", abc))
• unit tested
• clean commented code
• track breaking changes
• doc is rebuild (npm run doc)
• status is correct in Odoo

Forward-Port-Of: #1319

[robodoo]

Pull request status dashboard.

[fw-bot]

This PR targets saas-15.3 and is part of the forward-port chain. Further PRs will be created up to master.

More info at https://github.com/odoo/odoo/wiki/Mergebot#forward-port